i like to think of myself as a whiz at math, but this flow rate thing really confuses me. is there anywhere i can find out how many gph certain diameter tube will drain? i was thinking 1.5" or 2" lines. do i use the same size pvc for drain and return? also, when a pump is rated for gph, how do i figure out how many gph after the pump has to push the water so many feet high? i'm thinking it will be around 4' and probably a little higher. i'm assuming the wider the diameter the less gph. ( a 1" pvc at 4' will have a higher gph rate than a 2" pvc at the same height). i'm guessing that b/c of the increase in volume the pump will have to push. i have to upgrade my skimmer in the process. i have a hob seaclone that does a great job, all my levels have been 0, but i dont like the way it would work in-sump. i'm assuming all the flow rate revolves around the return pump? assuming this all pans out, drilling the tank, that is, my shopping list should start with the return pump, then skimmer. i think im going for a 30 breeder for my sump/ fuge. i want to make sure this is well thought out before i go spending money, breaking down tank, and drilling holes. if anybody has any flow rate numbers on pvc piping i'd greatly appreciate it. i guess there's no real difference in a 2" return line with ball valve or gate valve and a 1" pipe, except that with the 1" would limit the flow even more. i think i'll go 2". anybody have any idea's about number of drains/ returns, or info on closed loop?
